angular.module('batarang.scope-tree', []).

directive('batScopeTree', batScopeTreeDirective);

// TODO: tabindex
function newBranchElement(descriptor) {
  return angular.element([
    '<ol class="children expanded">',
      '<div class="selection"></div>',
      '<span>',
        '<span class="webkit-html-tag">&lt;</span>',
        '<span class="webkit-html-attribute">Scope #', descriptor, '</span>',
        '<span class="webkit-html-tag">&gt;</span>',
      '</span>',
    '</ol>'].join(''));
}

function batScopeTreeDirective($compile) {
  return {
    restrict: 'E',
    terminal: true,
    scope: {
      batModel: '='
    },
    link: function (scope, element, attrs) {

      // scope.$id –> DOM node
      var map = {};
      var selectedElt = angular.element();

      // init
      var scopes = scope.batModel;
      if (scopes) {
        Object.keys(scopes).forEach(function (scopeId) {
          var parentId = scopes[scopeId].parent;
          renderScopeElement(scopeId, parentId);
          renderScopeDescriptorElement(scopeId, scopes[scopeId].descriptor);
        });
      }

      scope.$on('scope:new', function (ev, data) {
        renderScopeElement(data.child, data.parent);
      });

      scope.$on('scope:link', function (ev, data) {
        renderScopeDescriptorElement(data.id, data.descriptor);
      });

      function renderScopeElement (id, parentId) {
        if (map[id]) {
          return;
        }
        var elt = map[id] = newBranchElement(id);
        var parentElt = map[parentId] || element;

        elt.children().eq(1).on('click', function () {
          scope.$apply(function () {
            scope.$emit('inspected-scope:change', {
              id: id
            });
            selectedElt.children().eq(0).removeClass('selected');
            selectedElt.children().eq(1).removeClass('selected');

            selectedElt = elt;

            selectedElt.children().eq(0).addClass('selected');
            selectedElt.children().eq(1).addClass('selected');
          });
        })

        parentElt.append(elt);
      }

      function renderScopeDescriptorElement (id, descriptor) {
        var elt = map[id];
        if (!elt) {
          return;
        }
        elt.children().eq(1).children().eq(1).html(descriptor);
      }

      scope.$on('scope:destroy', function (ev, data) {
        var id = data.id;
        var elt = map[id];
        if (elt) {
          elt.remove();
        }
        delete map[id];
      });

    }
  };
}

function repeaterPredicate (child) {
  return child.name && child.name['ng-repeat'];
}

function notRepeatedPredicate (child) {
  return !repeaterPredicate(child);
}